[Studies on changes in lymphocyte HL-A antigens during the course of malignant diseases].

The presence of HL-A antigens 1, 2, 5, 7, 8 and 12 on the lymphocytes of 26 patients with blood diseases and malignant tumours was examined by means of the two-step microcytotoxicity test. The studies carried out several times in the course of the disease and with 4 to 5 sera of the same specificity. Two types of the serological modifications were found: 1. Transient loss of HL-A antigens in 6 patients, 2. Evidence of the polyreactivity of lymphocytes in 3 patients. The polyreactivity was later changed to the loss of HL-A antigens. In one patient, the destruction of lymphocytes in the course of the testing was proved. The importance of the results is discussed. The additional serological, morphological and clinical investigations seems to be necessary.